A variety of scientifically defensible documents can be downloaded from EPA’s website

The U.S. Environmental Protection Agency (EPA) is providing information to assist risk assessors and scientists in the development of rigorous and scientifically defensible risk assessments for waterborne pathogens.

The document, a PDF file downloadable from the EPA website, describes a human health risk assessment framework for microbial hazards in water media (e.g., pathogens in treated drinking water, source water for drinking water, recreational water, shellfish water and biosolids) that is compatible with other existing risk assessment frameworks for human health and chemical hazards. Risk assessment is a science-based tool that is used to help managers explore the relative merits of various management alternatives, identify important gaps in knowledge and inform regulatory actions. This document does not address microbial indicators of fecal contamination such as E. coli, enterococci and bacteriophage.

The study and the production of this document was made under the Safe Drinking Water Act and the Clean Water Act, which address microbial contamination of the nation’s waters.

Programs under the two acts have historically followed separate paths using differing indicators of contamination and differing approaches. Concerns about future increases in microbial contamination and potential for emergence of new threats create a need to consider a strategy for the future that unites the influence of the two programs. Objectives of the strategy are to address all important sources of contamination, anticipate emerging problems, and use program and research activities efficiently to protect public health.